Merge branch 'master' into python-shebang

Author: KateFinegan

python-mutable-immutable/README.md

@@ -0,0 +1,3 @@
+# Python's Mutable vs Immutable Types: What's the Difference?
+
+This folder provides the code examples for the Real Python tutorial [Python's Mutable vs Immutable Types: What's the Difference?](https://realpython.com/python-mutable-vs-immutable-types/).

python-mutable-immutable/color.py

@@ -0,0 +1,8 @@
+from dataclasses import dataclass
+
+
+@dataclass
+class Color:
+    red: int
+    green: int
+    blue: int

python-mutable-immutable/immutable.py

@@ -0,0 +1,9 @@
+class Immutable:
+    def __init__(self, value):
+        super().__setattr__("value", value)
+
+    def __setattr__(self, name, attr_value):
+        raise AttributeError(f"can't set attribute '{name}'")
+
+    def __delattr__(self, name):
+        raise AttributeError(f"can't delete attribute '{name}'")

python-mutable-immutable/mean.py

@@ -0,0 +1,3 @@
+def cumulative_mean(value, sample=[]):
+    sample.append(value)
+    return sum(sample) / len(sample)

python-mutable-immutable/person.py

@@ -0,0 +1,17 @@
+class Person:
+    def __init__(self, name):
+        self.name = name
+
+
+class Student(Person):
+    def __init__(self, name, major):
+        super().__init__(name)
+        self.major = major
+
+
+john = Student("John", "Computer Science")
+print(type(john))
+john.__class__ = Person
+print(john.name)
+print(john.major)
+print(type(john))

python-mutable-immutable/point.py

@@ -0,0 +1,38 @@
+# class Point:
+#     def __init__(self, x, y):
+#         self._x = x
+#         self._y = y
+
+#     @property
+#     def x(self):
+#         return self._x
+
+#     @property
+#     def y(self):
+#         return self._y
+
+#     def __repr__(self):
+#         return f"{type(self).__name__}(x={self.x}, y={self.y})"
+
+
+class Coordinate:
+    def __set_name__(self, owner, name):
+        self._name = name
+
+    def __get__(self, instance, owner):
+        return instance.__dict__[f"_{self._name}"]
+
+    def __set__(self, instance, value):
+        raise AttributeError(f"can't set attribute {self._name}")
+
+
+class Point:
+    x = Coordinate()
+    y = Coordinate()
+
+    def __init__(self, x, y):
+        self._x = x
+        self._y = y
+
+    def __repr__(self):
+        return f"{type(self).__name__}(x={self.x}, y={self.y})"

python-mutable-immutable/point_collections.py

@@ -0,0 +1,9 @@
+import math
+from collections import namedtuple
+
+
+class Point(namedtuple("Point", "x y")):
+    __slots__ = ()
+
+    def distance(self, other: "Point") -> float:
+        return math.dist((self.x, self.y), (other.x, other.y))

python-mutable-immutable/point_typing.py

@@ -0,0 +1,10 @@
+import math
+from typing import NamedTuple
+
+
+class Point(NamedTuple):
+    x: float
+    y: float
+
+    def distance(self, other: "Point") -> float:
+        return math.dist((self.x, self.y), (other.x, other.y))

python-mutable-immutable/user.py

@@ -0,0 +1,6 @@
+class User:
+    __slots__ = ("name", "job")
+
+    def __init__(self, name, job):
+        self.name = name
+        self.job = job